RE: Warm-Blooded debate

["Michael" <tons@ccs.netside.com>]

> Date:          Mon, 16 Jun 1997 21:57:29 -0600
> Reply-to:      dwlewis@rmii.com
> From:          "Douglas W. Lewis" <dwlewis@rmii.com>
> To:            "'dinosaur@usc.edu'" <dinosaur@usc.edu>
> Subject:       RE: Warm-Blooded debate

> 
> 
> -----Original Message-----
> From: Jeffrey Martz [SMTP:martz@holly.ColoState.EDU]
> Sent: Monday, June 16, 1997 10:58 AM
> To:   Eric A Campbell
> Cc:   gsraptor@arkansas.net; dinosaur@usc.edu
> Subject:      Re: Warm-Blooded debate
> 
> 
> > They couldn't do this as ecotherms! Take the Komodo Dragon, for example.
> > It can run fast, as it has to, but it will sometimes pause in the middle
> > of a chase to catch it's breath. I severely doubt that a T. Rex would
> > have survived as a predator if it stopped in the middle of a chase.
> 
>      Komodo dragons seem to be getting by without starving
> to death.  Keep in mind if you are an ectotherm, you may not have as
> much energy for an extended chase as an endotherm, but at the same time
> you don't need to eat as much anyway so you get to have a few more
> unsuccessful chases.  Also keep in mind that if ALL dinosaurs were
> ectotherms, the theropods and herbivorous dinosaurs would have the same
> physiological limitations. 
> 
> > don't think that the 15-inch claw found on the _Utahraptor_'s foot would
> > be of much use if it was a scavenger. A slow ecothermic scavenger.
> 
> I'll put in something here. Utahraptor,15-inch claw or not,would need a lot 
> of energy to bring down a dino larger than it. Whether there was two of'em or 
> not. So I think that that would point more to>      For that matter,why were 
> all dinosaurs designe
d
 to be agile? If we take a look at modern day ectotherms,they're not designed 
to be very agile at all. Then why were dinosaurs designed to be more >        
From what I've seen,their design alone points to them being endotherms. Such 
as,their legs all bei
n
g underneath their bodies,only mammals have their legs this way. And as we all 
know,mammals a>      I personally do not see any evidence that dinosaurs were 
ectothermic.
> 
> Caleb
> http://www.geocities.com/Area51/Vault/6619/index.html
> 
I personally believe that at least some dinosaurs were endothermic.  
However, I disagree with your logic.  Crocodiles can come out of the 
water vertically almost their entire length to take prey.  They can 
make a rush up a steep bank several feet high and relaunch themselves 
after getting on top.  This may not apply to your definition of agile 
but it does mine.  My snakes are very agile at the right 
temperatures.  And very fast. There's many lizards even my middle son 
can't catch so I know they're agile.  So I don't think you can 
dismiss the controversy on ecto vs endo based on activity.  See 
Bakker's work on reptile activity.  A good textbook on animal 
physiology will help as well.

Michael